<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
<head>
<style>q:lang(en){
    quotes: "~""~";
} 
</style>
</head>
<body>
    <p>Some text <q lang="en">A quote in a paragraph</q> Some text.</p>
    <p>在本例中，:lang 为 lang="en" 的 q 元素定义引号：</p>
</body>
</html>